Wind turbines important for area's future energy needs
The rolling landscape around the small town of Arrowsmith – about 14 miles west of Gibson City – looks more like Holland than central Illinois.
Some 50 square miles of prime black farmland are dotted with windmills.
As gusts of wind blow over the corn and soybean fields, giant turbines convert the energy it creates into electricity. Each tower is 258 feet tall – taller than a 20-story building – with 8-foot-deep foundations.
When the Twin Groves Wind Farm is completed in December, it will become the second-largest wind farm in the country, with 240 turbines. The largest is the Horse Hollow Wind Energy Center near Abilene, Texas.
The $700 million farm is being developed by Horizon Wind Energy of Houston.
Twin Groves is expected to produce 400 megawatts, enough to provide power for 120,000 homes.
"I believe wind farms have the potential to be the future for energy here in the United States," said Mahomet resident Alvin Cargill, who serves as quality control manager for the farm.
Cargill said the turbines can generate electricity as long as the winds are blowing at between 12 and 55 mph.
Sensors at the top of each tower measure wind speed and direction.
If the winds blow at less than 12 mph, the turbines won't turn fast enough to make electricity. The turbines produce a maximum amount of electricity from 22 to 55 mph.
"The turbines automatically turn off when the winds exceed 55 mph and then will resume operations when the winds come back down again," Cargill said.
Cargill, 48, moved to Mahomet when he was hired to work on the project.
"I've got an RV, and Mahomet has one of the few RV parks that is open all year round," Cargill said. "Besides, Mahomet is a terrific community. I can't think of a better place around here to live."
Cargill said Horizon chose the Arrowsmith region because the land there is both flat and elevated, making the moraine ideal for capturing winds. In addition, a major electricity transporting line owned by Commonwealth Edison runs near the site.
Each turbine has an international flavor to it. While the tower sections were made in Shreveport, La., the blades came from Spain, and the hubs and cells were built in Denmark.
"Here's how it works," Cargill said. "The wind pushes the turbines. Each turbine has a transformer that catches electricity generated by the site.
"Underground lines buried 4 feet deep below the ground send the electricity to a substation. The substation then takes the electricity out to the grid."
Cargill said fiberoptic lines allow Horizon employees to control the operation of each turbine remotely from an operations and maintenance building on Illinois 9 and from Horizon headquarters in Houston.
"A farmhouse is being renovated to create some office space," Cargill said. "It will be like a visitor center, a place you can go to learn more about the technology."
While the electricity is distributed through Commonwealth Edison's transmission lines, Cargill said, Horizon can sell its wind electricity to anybody.
Cargill's job involves inspecting the 50 miles of roads that were built specifically for the project and the turbines themselves. About 220 to 250 people have worked on Twin Groves since June 2006.
Cargill and his wife, Carla, formed their own company, Turbine & Tower Enviro-Clean, which will provide portable washing crews to clean turbines at wind farms.
Their daughter, Mendie, leads one of the washing crews.
"There are three ways you can clean them," Cargill said. "You can clean them by rappelling. You can clean them with a pressure washer. You can clean them with a crane."
Cargill said his favorite time of day is in the early evening, when he can watch the windmills turn over the corn fields of Arrowsmith.
"When they start running, they are very relaxing," he said. "I like to sit and watch them."